Early last year, writer Maureen Orth learned an intriguing bit of trivia: A story she had written for Vanity Fair about Mia Farrow and Woody Allen at the height of their headline-grabbing breakup in 1992 was the fifth-most-read story in the magazine’s archives.

Orth also noticed that Farrow and her son Ronan were active on Twitter. Perhaps, she said, it would be “interesting” to revisit Farrow and her family and find out how they’d fared since the tumultuous events of nearly 22 years earlier. The Farrows agreed, and in April, Orth began her reporting, which culminated in an October piece about the family.

That simple sequence set in motion a chain of events that ended up propelling a sensational but long-dormant news story back into prominence, as a new generation discovered what an older generation had more or less forgotten about Woody Allen’s troubled personal life.

The Allen-Farrow saga from two decades ago included assertions that Allen had molested their daughter Dylan — a charge that a Connecticut prosecutor declined to pursue. The allegation gained new life first in Orth’s recent story, and then through social media. It culminated on Sunday, when the famously press-shy Allen took to the New York Times to deny, once more and at length, that he had abused Dylan when she was a child in the early 1990s.

The revived controversy has cast a new shadow over Allen’s legendary career. Allen’s reputation was damaged by the original allegations and widespread public revulsion over his romantic relationship with Soon-Yi Previn, Farrow’s then-20-year-old daughter. But all seemed to be forgiven, or at least forgotten, by the mid-1990s; Allen, who has been married to Previn for 16 years, went on to write, direct or star in more than 20 films.

Although few new revelatory details have emerged since the revival of the controversy, it has revived a debate about whether an artist who is alleged to have engaged in reprehensible behavior should be rewarded for his art. The issue comes up in the context of next month’s Academy Awards, in which Allen is nominated for an Oscar for the screenplay of his latest film, “Blue Jasmine.” Cate Blanchett and Sally Hawkins are also up for best actress and supporting actress, respectively, for the movie.

Orth, who disclaims any friendship with Farrow, says the family was initially reluctant to discuss the long-ago trauma. “I think I persuaded [Mia] to,” said Orth, an accomplished magazine writer who is the widow of “Meet the Press” host Tim Russert, in an e-mail. “She was not immediately keen.”

In the course of reporting her largely sympathetic story, Orth spoke with eight of Farrow’s 13 children. Her 9,400-word article contained the first lengthy interview with Dylan Farrow, now 28, who recounted in detail Allen’s alleged predation during a visit to her home in Connecticut more than two decades ago. Orth quotes Dylan Farrow as saying, ““If I could talk to the seven-year-old Dylan, I would tell her to be brave, to testify.”

But at least initially, the piece mostly got attention for another revelation: Mia Farrow’s acknowledgement that Ronan Farrow — born during Farrow’s relationship with Allen — may have been fathered by Frank Sinatra. The crooner had married Farrow in 1966 and divorced her two years later, but had remained close to her over the years, including during her time with Allen. Vanity Fair’s own publicity about the article highlighted the Sinatra angle, with Dylan Farrow’s comments given less prominence.

And it all might have died there, if not for Ronan, Mia and Twitter.

During the Golden Globe awards on Jan. 11, as Allen was about to receive a lifetime achievement award, Ronan Farrow tweeted: “Missed the Woody Allen tribute — did they put the part where a woman publicly confirmed he molested her at age 7 before or after [the clips of] Annie Hall?” he wrote.

Mia Farrow referred to Dylan’s accusations in the Vanity Fair article in a tweet two days later: “A woman has publicly detailed Woody Allen’s molestation of her at age 7. GoldenGlobe tribute showed contempt for her & all abuse survivors.”

The tweets set off a social-media storm. Between them, the Farrows have more than 600,000 followers; their tweets about Allen were retweeted thousands of times.

On Feb. 1, some 19 days after Ronan Farrow’s tweet, New York Times columnist Nick Kristof published an open letter from Dylan Farrow, raising the issue’s profile still higher.

“When I was seven years old,” she wrote, “Woody Allen took me by the hand and led me into a dim, closet-like attic on the second floor of our house. He told me to lay on my stomach and play with my brother’s electric train set. Then he sexually assaulted me. . . . I remember staring at that toy train, focusing on it as it traveled in its circle around the attic. To this day, I find it difficult to look at toy trains.”

Publication of the letter touched off a second social-media fury.

Finally, Allen weighed in on his own behalf, writing a column in the Times to address an issue he may have thought was buried two decades before.